There has heretofore been known a method for electrostatically collecting fine particles contained in a non-conductive liquid by creating an electric field in the liquid, intensifying field distortion, and disposing dielectric particle collecting members between electrodes to which voltage is applied. However, in the conventional device, fine particles adhered to the dust collecting plates flow away due to violent convection produced in the liquid by the creation of the electric field, or force exerted on the fine particles by the convection exceeds the electrostatic attractive force between the fine particles and the dust collecting plate, and the fine particles are scattered and float without being adhered to the dust collecting plate.
The inventor has found that if particle collecting plates of fibrous materials, such as for example paper, are arranged so as to be in parallel with the direction of an electric field, influences by the convection are significantly reduced so that fine particles can be caught and collected with an extraordinarily high efficiency.
This invention has been made on the basis of the knowledge as stated above, and has for its object to provide purifying equipment capable of purifying a large quantity of liquid with high efficiency.